Monday, December 20, 2010

DETROIT (AP) — An effort to fight an invasive plant with insects that eat it has drawn opposition from beekeepers who worry it will leave them without an adequate source of nectar and pollen for their honeybees.

Researchers in Michigan released bugs that feed on spotted knapweed earlier this year. Western states and big honey producers, such as Minnesota and Wisconsin, previously used so-called biological control to help restrain the flowering plant, which produces chemicals that deter the growth of other plants and crowds out native vegetation.

It's not clear why Michigan beekeepers are so worried about knapweed control when those in other states haven't been as much. Some in the industry speculated Michigan beekeepers may rely on knapweed more for nectar and pollen than those in other states. Regardless, Michigan is among the nation's top 10 honey producers and the home of beekeepers who ship hives as far as Florida and California to pollinate orchards and fields. Beekeepers argue that if they're hurt, the farmers who rely on them will suffer too.

"If it wasn't for this plant, we wouldn't even be here," said Kirk Jones, the 57-year-old founder of Sleeping Bear Farms in the northwest Lower Peninsula community of Beulah. If knapweed control efforts prove successful, he said: "It could be detrimental to the future of the beekeeping industry."

The dispute between the state and its beekeepers is happening amid a massive die-off of bees nationwide. Colony collapse disorder has killed about 30 percent of the nation's bees each year since it was recognized in 2006, according to a report the U.S. Department of Agriculture released Friday. The bees are crucial for the production of 130 crops worth more than $15 billion a year, it said.

Michigan officials said they're keenly aware of the importance beekeepers place on knapweed, which blooms in late July and early August when many other plants aren't flowering. As part of the knapweed fight, they're looking at what kinds of native flowers could be planted to replace it — both to sustain bees and improve the diversity of wildflowers statewide.

"It's not an attempt to take away a resource that beekeepers find valuable, but to replace it with one that might have more functionality," said Ken Rauscher, director of the pesticide and plant pest management division for the Michigan Department of Agriculture, which worked with federal officials to oversee the release of knapweed-eating bugs.

Beekeepers, however, are skeptical about other flowers' ability to do the job.

Spotted knapweed, also known as starthistle, was introduced in the U.S. from Europe in the late 1800s. It was brought over accidentally, either in contaminated seed or ships' ballast water, according to the U.S. Department of Agriculture. The plant has been seen in Michigan for at least a century but has spread more vigorously in the past two decades. It thrives in sandy soils, such as dunes, and in former farm fields, along roads and in prairies.

Many beekeepers have set up shop near large expanses of knapweed, said Roger Hoopingarner, president of the Michigan Beekeepers Association. Its loss, and a subsequent loss of bees, would hurt honey production, but the bigger effect would come from not having bees to pollinate fruit and vegetable crops, he said.

Michigan is second only to California in the diversity of crops it produces and is among is among the nation's leaders in the production of red tart cherries, apples and blueberries — all of which need pollination.

"If spotted knapweed goes away and there is nothing that will replace it, then some of these beekeepers . . . will just leave the state," Hoopingarner said. "They go now to California or other states for pollination, and they won't come back because there will be no incentive to come back."

Two knapweed-eating flies were released in Michigan in the 1990s, but those don't appear to have curbed its spread, Rauscher said. So in August, researchers released two types of weevils on state land in five counties. Scientists in other states have found success in killing off knapweed with a combination of flies and weevils.

Michigan officials don't expect to wipe out knapweed; the hope is to pare it back. Doug Landis, a Michigan State University professor who specializes in biological control, is working with the state on the project. He said replacing knapweed with other flowers is a must because of the way Michigan beekeepers use the plant.

"That will maintain the nectar flow," Landis said.

Terry Klein, 70, of TM Klein and Sons Honey in St. Charles, has about 1,000 colonies of bees in central Michigan. He said he fears the economically-troubled state won't have the resources needed to fully replant areas where knapweed is killed off. The burden will be on beekeepers, who will have to raise the prices they charge Michigan farmers for pollination, he said.

The pilot project will be evaluated over the next year or two, and Michigan officials don't expect to release more insects until that is done, Rauscher said. Even if the project is expanded, it could be 10 to 15 years before the bugs have a substantial impact on the presence of knapweed, leaving time for beekeepers to adjust, he said.

And, the Michigan Beekeepers' Hoopingarner added, even if Michigan doesn't introduce more bugs, they could eventually spread there from surrounding states where they're used to control knapweed.

A study by Elena Litchman, Michigan State University associate professor of ecology, sheds light on why invasive microbial invaders shouldn’t be overlooked or underestimated.

“Invasive microbes have many of the same traits as their larger, ‘macro’ counterparts and have the potential to significantly impact terrestrial and aquatic ecosystems,” said Litchman, whose research appears in the December issue of Ecology Letters. “Global change can exacerbate microbial invasions, so they will likely increase in the future.”

The public and scientists seem to be well-informed of the spread of Asian carp, zebra mussels and gypsy moths – all invasive macroorganisms. But what about exotic cyanobacteria, also called “blue-green algae,” which have found their way into North American and European lakes? Or a nitrogen-fixing rhizobium, a soil microorganism that has emigrated from Australia to Portugal?

In the Great Lakes, a brackish diatom (a microscopic alga), has colonized Lake Michigan probably via ballast-water discharge and is now the largest diatom in the waterways. How will it change the ecosystem? What changes has it caused already?

While many people have a working knowledge of the American chestnut blight, which was caused by a pathogenic parasitic fungus, most invasive microbes fly beneath the radar of the public and scientists alike. Virtually nothing has been published on the potential of nonpathogenic microbes on a large scale, according to Litchman.

“From scientific research, we know that the chestnut blight dramatically altered forests and how the spread of West Nile virus is associated with significant bird die-offs,” she said. “Currently, there are no published examples of the impacts of invasive nonpathogenic microbes, but there is growing evidence that they could change ecosystems in equally dramatic fashion.”

The lack of attention to microbial invasions compared to macroorganisms is due, in part, to their cryptic nature and the difficulty of detection. Lack of detection combined with climate change could potentially exacerbate these microbial invasions, which could continue to grow as the earth’s weather patterns change, Litchman added.

“Increasing air temperatures have been implicated in the spread of malaria and other pathogenic microbes into higher altitudes and latitudes,” she said. “Likewise, climate change could stimulate invasions by tropical and subtropical nonpathogenic microbes into temperate latitudes.”

Litchman’s research is funded in part by the National Science Foundation.

APHIS is amending the regulations governing the importation and interstate movement of noxious weeds by adding definitions of terms used in the regulations, adding details regarding the process of applying for the permits used to import or move noxious weeds, adding a requirement for the treatment of Niger seed, and adding provisions for petitioning to add a taxon to or remove a taxon from the noxious weed lists. These changes will update the regulations to reflect current statutory authority and program operations and improve the effectiveness of the regulations. We are also adding seven taxa to the list of terrestrial noxious weeds and to the list of seeds with no tolerances applicable to their introduction. This action will prevent the introduction or dissemination of these noxious weeds into or within the United States.

About Me

I am a consulting ecologist specializing in ecological restoration, invasive species, and conservation planning.
I have a 20-year background in natural resources management, including nine years with The Nature Conservancy on Long Island as Invasive Species Project Director. Past employers include the New York State Department of Environmental Conservation (NYSDEC), Natural Land Institute, and Onondaga County Parks. I have an M.S. degree in forest resources management from the SUNY College of Environmental Science and Forestry (ESF) at Syracuse. Most importantly, I have three wonderful children: Erin, Cara, and Willy.
This is my personal blog; the views expressed here are my own.
To contact me regarding invasive species, please e-mail me at bjacobs@geiconsultants.com